Ideally, this proposed water injection system would be actived by knocking. Is anyone aware of any knock detection schemes/devices for the 400????
Failing this, those of you who would like to design your own based on other engine sensors (RPM, TPS, Vacuum etc), there is a neat little product for about $35.00?? called The Basic Stamp" from http://www.parallax.com/ that would provide the control functions.
Best of luck for someone to do this right and share it.... it is an idea that has merit.

 

Ecuri, thanks for your insight. i don't want it to be knock initiated since I want to advance my timing along with the water-injection for more power and better mileage.
The Basic stamp this has merit but since I had to read the web site just to figure out what a stamp was, I think it is beyond my meager knowledge of electronics.

Thanks
Clint

 

coulndnt you run a belt driven pump off the engine, then as the rpms went up so would the pressure? also wouldnt a old nitrous plate work with the spraybars and the ability to change the jets for tuning reasons?

 

if you use a electric pump could you use a headlight switch to run it? they have a reostat built in to dim the panel lights when you turn the ****. will an electric 12v pump even run if you lower the voltage? i have a variac in my shop it works good on some electric motors to slow them down but others just stop.

 

another thought is to maybe use a couple old fuel injectors if you were good enough with electronics you could probably use a tachometer to trigger them and you could feed them with a high pressure pump, any way you go though i would use a oil pressure saftey switch to keep from pumping water into the engine while it is not running

 

Howdy! 71swissaqua,

Getting lots of good ideas on this subject!

 

Hi Guys, I'm getting into this pretty late, hope you guys will keep this going as its pretty interesting to follow. Years back ( mid - late 70's ) Hot Rod magazine did an article about building a homebuilt water injection system, All I remember about the article is they used something called Hobbs switches ( a type of vacume switch ) that apparently you can get with different vacume values to make it work. I seem to remember that it used 2-3 differerent Hobbs switches depending when you wanted it to kick in, and how much. Sorry thats all I remember, but maybe someone might have an old stash of magazines they could find it in. Another option, maybe using www. findarticals.com? I've used this before but its been awhile. AL

 

A Hobbs switch can be had in either vacuum or pressure versions "for blowers" as I understand it. It activates on vacuum drop when you step on the throttle and I believe they are usually adjustable.

The nice thing about the aftermarket units is they use a computer to not only turn the injection on/off but can also vary the rate according to load.

 

Your'rr right about the aftermarket ones being better. I've been trying to figure out a way to vary the output of the pump in a DIY method but have about giving up. There are several DIY versions in a kit form that may be worth looking at though. One is at www.Autospeed.com
I think I'll look into the Hobbs switches alittle more
Clint

 

Really an interesting posibility if someone can come up with an easy to build dependable system that will also benefit the mild daily driver.
I was also curious as to what effect if any the water vapor will have on the catalitic converter. Several of you are running water, has it effected your cat?
What about hyperutectic pistons?
Wish I had more to offer than more questions but I feel answers to them are part of the solution.

 

try this site. www.journeytoforever.org/biofuel_library/ewthanol_motherearth/me3.html
it supposed to be spliced into your dizzy vac line and suck the mist out of the bottle. I'll bew testing mine out today

 

"APO MARK II VAPOR INJECTOR KIT . I AM TOLD THESE WERE USED ON CORVAIR AND OTHER AIR COOLED MOTORS TO RUN COOLER AND INCREASE HP. I DON¡¯T KNOW HOW TRUE THAT IS. "

Never heard of this product?

 

I've been using a Spotlyte ag-sprayer pump built by Sureflo(3/8 fpt ports). It has an adjustable, integral pressure switch built in. I use stainless mist nozzels from Arizona mist company. The suction side of the pump uses 3/8 fuel vapor line. On the pressure side I use the plastic tubing that comes with the garden mister. I like the system with the flow through brass tees. The stainless nozzels scew in to the tees and are easily removed for cleaning. Arizona sells brass plugs to close off any tee in the system. The tubing is press to connect, leakproof The pump is powered off my battery charge relay with oil pressure cut-out. I would not try to regulate the pump rpm speed. Just let the pump maintain constant pressure in the nozzel supply line(s). The pump will cycle automatically to maintain constant pressure. Yow want constant presssure so you'll have a fine mist. The pump will click on for just a second at a time to run one nozzel. An electric solenoid water valve is inserted in the the water line on the output side of the pump. When it's closed the pump will shut off by itself. The trick is to modulate or pulse your solenoid water valve with electrical signals from engine rpm or vacuum switches(not the pump motor speed). You can add mist nozzels and lines by teeing off the pump output. This lets you have a mist cooling system for hot weather driving/towing and makes for a dual purpose system. Just use manual valves or solenoids to direct the water supply to either/both the water injection or the radiator mist cooler as needed. Any component can be cooled with mist. Transmission coolers/housings, p/s pumps, ect.

 

has anyone actually used a Holley or Edelbrock water injection system? I have access to both. I have an aging 400 that is worn enough to be my experiment motor and I would like to try water injection to hopefully be able to advance the timing more. Which kind is better? I already have a Holley kit, that was never installed but I want opinions of each brand. Would the fact that a stock 400 is low revving make a difference whether water injection can be used reliably?